There are several medical conditions which can benefit from implantation into a patient of a filler material, an embolization coil or other device, whether temporary or permanent. Examples include the closure of blood vessels or other lumens. One condition for which such procedures can be particularly useful is in the treatment of aneurysms, where a part of a vessel wall weakens and expands outwardly to create an enlarged zone of the vessel, often having the form of a sac. This vessel expansion occurs as a result of blood pressure and tends to continue due to further and progressive weakening of the vessel wall. If left untreated, persistent pressure from the blood flow on the weakened wall tissue can lead to eventual rupture of the vessel and consequential haemorrhaging. Treatments for aneurysms have tended to focus on reducing the pressure on the weakened vessel wall, for instance by diverting blood flow or by isolating the weakened vessel wall, for instance by means of a stent graft. Another treatment method involves filling the aneurysm sac with a filler material which stops the flow of blood into the sac and as a result stops or substantially reduces the pressure on the weakened walls. The filler may be an embolization coil, which will cause static blood around the embedded coil to clot, which blocks the sac and creates a protective barrier to prevent vessel rupture. In other methods the aneurysm may be filled with a biocompatible material, such as a hydrogel or a polysaccharide fibre, which may be of a biodegradable nature. A biodegradable filler performs the same function as an embolization coil, that is to fill the aneurysm sac and provide pressure protection to the weakened vessel walls, with the additional advantage of allowing remodeling of the vessel wall over time. Moreover, biodegradation of the filler will ensure that no foreign matter remains in the patient's vessel after conclusion of the treatment.
A useful technique involves the administration of a filamentary filler material, which can be delivered endoluminally through a small diameter catheter. The filamentary material is biocompatible and potentially also biodegradable. In many instances it is optimal to use filamentary material having a very small diameter, which enables the use of a narrow diameter delivery catheter, useful for delivery through and into small diameter vessels, for filling small aneurysm sacs, and so on. However, narrow diameter filaments can be difficult to handle, both into the delivery apparatus and from the delivery apparatus into the delivery catheter. Similar problems can also be encountered with biological or similar filamentary material, such as material made from small intestine submucosa (SIS), which can be difficult to handle especially in filamentary form.
Examples of endoluminal filament and coil delivery systems can be found in U.S. Pat. No. 6,458,137, U.S. Pat. No. 5,476,472, U.S. Pat. No. 6,379,329, US-2003/0225391, US-2011/0077681 and US-2013/0296917.